What is poly gamma glutamic acid in skincare?

What is poly gamma glutamic acid?

PGA is a naturally occurring biopolymer, meaning a long chain of repeating biological building blocks. It dissolves in water and is biodegradable. Most commercial PGA is produced through microbial fermentation. PGA and glutamic acid are related but are not interchangeable names: glutamic acid is an amino acid, while PGA is a chain made from those units.1

What does PGA do in a moisturizer?

PGA can serve as a humectant and a thickener. Those are different jobs: one concerns moisture, while the other concerns the consistency of the formula. Polymer size, concentration and the surrounding conditions influence PGA's properties, so the ingredient name alone does not tell you how a finished product will feel.1

A moisturizer can combine humectants with emollients, which soften and smooth skin, and occlusives, which reduce water loss by forming a protective surface layer. Moisturizing can reduce dryness and make fine lines less noticeable. Claims about reducing signs of skin ageing can be misleading, even when the packaging seems extremely sure of itself.2

Which formula should you choose?

Choose the finished moisturizer for your skin's dryness and the texture you can use comfortably. A moisturizer earns its place by helping with dryness, not by making the ingredient list sound like a chemistry entrance exam.3

How should you use it?

These are general moisturizing steps, not a special PGA dosing schedule.

1. 1Apply a moisturizing cream or lotion immediately after bathing, while skin is still damp, to help retain water.
2. 2Adjust application to the degree of dryness. Slightly dry skin can need only a light moisturizer at night; drier skin needs more frequent moisturizing.
3. 3For combination skin, focus moisturizing on the dry areas rather than automatically covering oily areas with the same amount.

What should you expect?

Judge a moisturizing formula by reduced dryness and improved comfort, rather than expecting a permanent change from one application. General moisturizer benefits are greatest during the first six hours after application, and regular application two to three times daily can be needed. A best facial PGA percentage, a specific result timeline and instructions for pairing it with prescription treatments remain unsettled.2

Who should be careful?

Sensitive skin can react to a moisturizer's fragrances, preservatives or other components. Avoid fragranced formulas if your skin is dry or sensitive. Stop a product if contact dermatitis, an inflammatory skin reaction, develops. If dryness becomes painful, cracked, bleeding or persistently irritating, see a dermatologist. Pregnancy specific advice for facial PGA is not settled.23

Does PGA have uses beyond moisturizing?

PGA also functions as a lubricant in contact lens care formulations. Antimicrobial activity has been investigated in a specific formulation combining PGA with chlorine dioxide. For facial skincare, keep the purpose focused on moisturizing rather than choosing PGA as an acne treatment.4

What is glutamic acid good for?

Glutamic acid is a nonessential amino acid, meaning the body can make it. Amino acids are building blocks of proteins. Its role in the body is separate from the moisturizing use of the PGA polymer.56

What does glutamic acid do?

Glutamate acts as an excitatory neurotransmitter, a chemical messenger that helps nerve cells pass signals onward. It is the most common excitatory neurotransmitter in the brain and plays a major role in learning and memory. These are functions of glutamate in the body, not reasons to apply a PGA moisturizer.67